MRZS-S

Performs the following functions

Control and measurement

• phase currents at a frequency of 50 Hz with a nominal value Iн = 5 A in the range from 0.1 to 30 Iн;
• currents of positive and reverse sequences;
• three phase or line voltages of the first bus section - up to 150 V;
• three phase or line voltages of the second busbar section - up to 150 V;
• angles between all analog line measurements;
• network frequencies;
• active power with a sign;
• reactive power with a sign;
• full power;
• power factor;
• inter-phase active and reactive resistances.

Relay protection functions:

• four-stage overcurrent protection (OCP), has the following stages:
• 1 stage with definite time delay (current pinch-off), or with the possibility of a voltage triggering, or directional OCP with an independent time delay;
• 2 stage with an indefinite time delay with the possibility of voltage triggering or with a definite time delay (in accordance with IЕС 255-4 types A, B, C, characteristics RТ-80, RТV-1), or directional OCP with indefinite time delay;
• 3 stage with a definite time delay (overload protection) with the possibility of voltage triggering or directional OCP;
• 4 stage with a definite time delay (overload protection) with the possibility of voltage triggering or directional OCP.
• blocking of the OCP from magnetizing current surges
• negative phase-sequence protection (NPSP), reacts to the ratio of the negative sequence current to the positive sequence current (phase failure monitoring (PFM));
• arc fault protection (AFP): AFP launch is carried out through a discrete input or from external fiber-optic arc protection sensors with the ability to control phase currents, voltages in any combination or 3Io;
• two-stage undervoltage protection ЗНmin;
• two-stage overvoltage protection ЗНmax;
• circuit-breaker failure protection (CBFP) with current control: breaker failure protection is initiated at OCP response to cut-off or via discrete input. The breaker failure protection has two stages in response time;
• universal protection (8 ps.) with the possibility of starting with phase currents, I1, I2, phase or line voltages, U1, U2, active, reactive and full power. In this case, the fault detector can operate both on the excess of the setpoint and on a decrease below the setpoint.
• the de-shunting function of two current circles

Automation functions:

• circuit breaker control. The circuit breaker can be switched on and off both from the device and via a discrete input (pulsed). If there is a command to cut off the circuit breaker, the on signal is blocked;
• acceleration of protection. The automatic acceleration of the OCP of the second stage is entered at the command of the circuit-breaker;
• four-time recloser (AR). The AR is started from the OCP. If a blocking signal is present at the discrete input, the inhibition of the reclosure is carried out, if it disappears, the inhibition of reclosure is removed;
• synchronism control;
• ACB with the possibility of starting from lowering and increasing the voltage.

Monitoring, registration and alarm functions:

• determining the fault location;
• circuit breaker closing and opening monitoring;
• control of commutation life of switch;
• emergency registrar of oscillograms of currents with recording of discrete signals:
• parameterizable duration of pre-emergency and emergency recording;
• resolution capability of the recorder by analog signals - 1,25 ms;
• total recording time - 50 s.
• discrete signal recorder:
• 30 recent events;
• up to 43 records in each alarm with a fixed value:
• maximum phase current;
• maximum phase or line voltage;
• minimum phase or line voltage;
• maximum ratio of the current of the negative sequence to the current of the positive sequence;
• statistics recorder: records the last 400 changes of all discrete signals
• Energy metering:
• active energy
• in two directions; reactive energy;
• in four quadrants.
• Short-circuit current auxiliary power supply. If the power supply of the device at the power input of 220 V (or 110 V) The device can be powered from current transformers of phases A and C. In this case, the magnitude of the current must be 4 A or more for one of the phases or for the total of two phases.

Supply of two discrete inputs from internal power source (DIР)

Enhanced logic functions:

• number of defined functions - 8;
• number of defined triggers - 4;
• status of triggers is stored in non-volatile memory;
• transfer functions;
• logical elements AND, OR, NOT, EXCLUSIVE-OR.

Enhanced logic allows to complement existing functions and create new ones.

Service functions:

• freely assignable inputs;
• freely assignable outputs;
• freely assignable LEDs;
• four groups of settings for all protections;
• monitoring the integrity of the sensors and the arc protection path;
• multilingual menu - 3 languages supported;
• six freely programmable buttons with the ability to operate in key mode;
• switch control buttons;
• work with an external computer is carried out through the USB port.

Interfaces and communication protocols:

• Interface RS 485 - Communication protocol Modbus RTU;
• Interface USB;
• Interface by choice:
• Interface Ethernet (RJ-45)- Communication protocol IЕС 61850 (optional);
• Interface Ethernet (optic) - Communication protocol IЕС 61850 (optional).

	G	H	J
Current sensors	3I	3I	3I
Voltage sensors	6U	6U	6U
Short-circuit current auxiliary power supply	+	+	+
Voltage output for discrete inputs power supply (DIР)	+	+	+
Number of LEDs, of them programmable	20 17	20 17	20 17
Function keys, of them with key mode	6 6	6 6	6 6
Switch on and off buttons	+	+	+
RS485 communication interfaces USB	1 1	1 1	1 1
variable data for hardware configuration	#colspan#	#colspan#	#colspan#
Number of discrete inputs	16	16	16
Number of discrete outputs: with NO contact element with change-over contact power	16 8 6 2	16 8 6 2	16 8 6 2
Optical arc control inputs	- -	3 +	3 +
Interface Ethernet (optical or wired)	-	-	1